Previous sacral nerve stimulation needles typically include a stylet removably disposed within a cannula, wherein a stylet hub is press fit or snapped into engagement with a cannula hub to locate the stylet in place within the cannula. A proximal end of the cannula includes a first uninsulated portion (distal from the cannula hub) for temporary attachment to a stimulator device in order to perform trial stimulations in a patient or other subject. The trial stimulations are delivered to the patient or other subject from a second uninsulated portion at a distal end of the cannula, the second uninsulated portion being spaced from the first uninsulated portion.
Previous sacral nerve stimulation needles include several disadvantages. One such disadvantage is with removal of the stylet from within the cannula. In order to remove the stylet, one must grip the cannula with one hand and pull on the stylet hub with the other hand, creating forces in opposing directions (distally and proximally) and potentially causing the cannula to move with respect to the patient or other subject, thereby potentially losing the optimal stimulation position. Another disadvantage of previous sacral nerve stimulation needles is that, by clipping the stimulator device to the proximal end of the cannula for trial stimulations, the overall working length of the needle is decreased because at least the first uninsulated portion at the proximal end of the cannula must be exposed in order to attach the stimulator device to the cannula.